This entry describes packed brown sugar. The word “packed” is part of the measurement, so an unpacked cup should not be treated as the same starting quantity.
Follow the selected packing instruction
The King Arthur record covers packed light or dark brown sugar under its source convention. Women’s Weekly Food supplies a firmly packed, level 250 mL cup reference.
Neither reference supplies a quantified packing force that makes every kitchen measure identical. Keep the result approximate and follow the selected method rather than inventing an adjustment between loosely and firmly filled cups.
Keep the source relationship intact
The King Arthur source cup has no established millilitre definition in the consulted material. The Women’s Weekly Food reference has an explicit 250 mL basis. Select the reference that fits your recipe before changing the output unit.
If the recipe gives a weight, enter that weight directly. Packing is then a preparation detail, not a missing factor in the gram-to-gram scaling calculation.
Retain useful sugar details
Keep a light or dark sugar preference in the row note even when the source groups them. A shopping total should preserve the description you need to buy the intended ingredient.
Before exporting, check that “packed” has not disappeared from a cup-based amount. Someone reading the output needs the measuring instruction as well as the number.